Agronomist Notes

Another snow event, cool temperatures and rainfall slowed down seeding progress in many areas last week. It seems like the south and eastern portion of the province is well behind while producers in the west and northwest are well ahead of schedule. At this time last year we were more than half finished seeding. For myself, not a wheel has turned yet but we certainly hope to this week, if the weather holds.

I’ll keep this week’s newsletter brief as many of you are in the field this week. I’ll start with some tips to help you through the week, and then on to optimizing plant densities to increase maturity. Next, we’ll crunch some numbers on the value of hiring a custom applicator to do some spraying for you this spring.  We’ll also look at why rapid emergence and development is so critical in the first 45 days. Last, I’ll outline the effects of spring frosts on cereal crops and look at the factors effecting frost tolerance and how to scout for damage. Fundamental and technical grain market news ends the issue.

Barley seeded on April 25th near Drumheller, Pliva Ag Production Ltd.

Agronomy

Steve’s tips for the week

Keep an eye on fields you’ve marked for a post-seed herbicide application. Don’t take your eye off the ball while you’re busy seeding. Call in the custom applicator for a few fields if you have to; I wouldn’t jump off the drill to go spraying.

Wait 6 hours before seeding after glyphosate application if you’re targeting annual weeds and 72 hours if you’re targeting perennials. 

Increase seeding rates by 10% after May 15th. So, for those who normally target 24 plants/ ft2, you may want to increase your target to 27 plants/ ft2. Those of you who target 28 plants/ ft2 can increase that target to 31 plants/ ft2. With an average seeding rate of 130 lbs/ac at a treated cost of $0.16 a pound, the additional $2.08 an acre is more than worth the investment if you can turn a No. 2 or 3 grade into a No.1.

If you have wheat or barley emerging with a flush of volunteer canola coming, pull the florasulam out of the Pre-Pass and apply without the glyphosate but add 50 ml/ac of a non-ionic surfactant. Or, apply Express SG with 50 ml/ac of a non-ionic surfactant at 5 gal/ac water volume. 

In spite of the frosts, which seem to occur daily, look at the appearance of the weeds to know if they are actively growing and whether you can go spraying. Pale green, wilted or yellow appearance is a no, perky and green is a go. Look for temperatures above 8 degrees C for at least two hours before spraying a pre-emergent like glyphosate. SL

Optimize maturity with custom seeding rates

Whether or not your seeding has been delayed this spring, it’s vitally important to optimize your plant stand densities to avoid maturity delays. As we know, a thin plant stand can lead to excessive tillering and delayed maturity. A plant will develop a leaf or tiller every three to five days after emergence depending on temperature and moisture. If you provide a plant with enough room to grow by reducing the competition within each row, it will continue to produce tillers. For example, a wheat plant may produce an additional two tillers in a non-competitive environment. If that plant takes three to five days to produce each tiller, the maturity of that plant will be reduced by six to ten days when compared to a plant that has adequate inter-row competition through optimum seeding rates. Remember, 50% of your yield comes from the main stem and 50% comes from the next two tillers. Any more than two tillers on a wheat crop is a waste of energy and maturity. 

To give you an example why the 2 bushel an acre seeding rate rule can leave you with excessive tillering, have a look at the table below. Here I have 9 samples and 3 varieties of wheat ranging from 46 grams to 35 grams per 1,000 kernels. For my clients, I’ve targeted a plant stand density of 30 plants ft2 with seeding rates ranging from 151 lbs/ac to 113 lbs/ac. If you look at the table you can see that if I recommended a 2 bu/ac seeding rate, we’d be 20% under the mark with CDC Go and 6% over with Unity. There wouldn’t be enough plant competition with CDC Go and there would be too many plants seeding Unity at 2 bu/ac.

Successful farming is about optimizing a hundred little things. A simple boost in plant stand density can help produce higher yields while reducing maturity. For those of you who are delayed this year and will be pushing the limit on maturity, stop guessing and start measuring. SL

Seeding rate (lb/ac) = desired plant population/ft² x 1,000 K wt. (g) ÷ seedling survival rate (in decimal form such as 0.90) ÷ 10.4

Should I hire a custom applicator to help with pre-burn?
Many of you who’ve been delayed on seeding will be deciding whether to stop the drill to spray or leave the application until after you’ve seeded. In a perfect world where no yield loss would occur from a delay in seeding, the drill would be parked and we’d be off spraying. But considering the tight timeframe we’re in this spring, I think you might be money ahead to continue seeding and hire the custom applicator to do a pre-seed or post seed burn off on a few fields.

In my analysis here, I’ll assume that you can seed 300 acres per day, the custom applicator costs $6.00 acre, yield loss in wheat, barley and canola is 1% per day, and are valued at $4.60 bu, $3.00 bu and $9.00 bu, respectively. Average yields are 50 bu/ac wheat, 80 bu/ac barley and 40 bu/ac canola.

Steve’s quick math

Custom applicator: $6.00/ac
Producer cost with 90 ft self-propelled: $1.90/ac
Yield loss wheat: 1% x 50 bu/ac x $4.60/bu = $2.30/ac 
Yield loss barley: 1% x 80 bu/ac x $3.00/bu = $2.40/ac  
Yield loss canola: 1% x 40 bu/ac x $9.00/bu = $3.60/ac 

If you were to lose one day seeding because you had to stop the drill and go spraying it would cost you:

Wheat: $6.00/ac custom app - $1.90/ac your cost - $2.30/ac yield loss = $1.80/ac
Barley: $6.00/ac custom app - $1.90/ac your cost - $2.40/ac yield loss = $1.70/ac
Canola: $6.00/ac custom app - $1.90/ac your cost - $3.60/ac yield loss = $0.50/ac

Therefore, in this example, it would cost you between $0.50 to $1.80 acre to hire a custom applicator when you factor in your own spraying cost and the potential yield loss at this time of year. I realize the $6.00 or $7.00 price tag for custom app seems high but when you look at the opportunity cost of spending your time seeding instead of spraying, hiring it out may be your best option. If anything, it can get you through in a pinch. I see Fox Coulee Aviation out of Drumheller is advertising pre-seed glyphosate applications. Food for thought. SL 

High temperatures during tillering reduces yield

I think we’ve all heard that the first thirty days in a crops life is critical. In fact, on average we will lose 1% yield for every day we delay wheat and barley seeding past May 15th. We’ve been told that pushing grain filling out into the hotter part of the summer will reduce yield but did you know that moderately high temperatures during tillering will reduce kernel formation?

In cereals, the main factor contributing to yield reductions after delayed seeding is the potential for higher temperatures during tillering. The number of kernels per head decreases whenever the maximum daily temperature climbs above 170C during this specific growth stage. If we push the tillering stage out to late June instead of early June we run the risk of higher temperatures and a reduction in the number of kernels each head will produce. 

With this knowledge, it’s important to do everything you can to ensure rapid emergence and development. By now you all know my thoughts on seeding speed, precision drills, phosphorus placement, calculating plant stand densities, applying nitrogen separately and away from the seed row, inter-row seeding, planting north south, minimizing compaction, dualling up the air carts and a number of other measures we can use to improve emergence and development. SL

For more tips on improving maturity at seeding go to:
http://www.beyondagronomy.com/newsletter/15_5_2007.htm
http://www.beyondagronomy.com/newsletter/13_5_2008.htm

Frost damage on cereals

I’ve had a number of questions on the effects of hard frosts on emerging cereal crops. Overnight temperatures continue to drop below zero with -3 to -8 degree frosts not uncommon which is making some producers a bit nervous. To help you understand what to expect after a hard frost I’ve outlined the factors that affect a cereal crops tolerance to spring frosts.

Temperature alone does not accurately predict the level of damage a crop might see. Several factors come into play like crop tolerance, growth stage, soil moisture content, duration of the frost, location in the field, and environmental conditions before the frost occurred. Also, there is considerable variation for tolerance between crops. In general, if all crops are in the early stages of development the tolerance to freezing temperatures from most tolerant to least tolerant are fall rye, winter wheat, oats, barley then wheat.
 
Growth stage:

• Cereal crops can tolerate early spring frosts because their growing points remain below the soil surface for several weeks after emergence.
• In small grains the growing point extends above the soil surface at about the 6 leaf stage or just prior to the first node or jointing.
• Winter wheat is more susceptible to frost damage because its growth stage is further advanced. I would recommend that you carefully inspect growing points in your winter wheat if you had temperatures below -4C degrees for any extended period of time. The growing point is more susceptible to damage than leaf tissue during jointing. A damaged growing point will appear brownish or water soaked. A dead leaf may appear in the whorl if the growing point has been damaged.

 
Environmental factors:

• Temperatures change more slowly in wetter soils than in dryer soils. Therefore, there is more risk of low temperatures killing plants if your soils are also dry.
• Plants are capable of hardening themselves against freezing and plants that had previously been exposed to near freezing temperatures are more likely to tolerate lower sub-freezing temperatures than those that have not.
• Most of the cereal crops were probably at least partially hardened before the arrival of the coldest weather last week and this may explain why there is less reported damage to cereals than was anticipated.
• Cold air is heavier than warm air, so cold air will flow towards the lowest parts of your field, making frost damage more severe in these areas. When assessing frost damage, I would suggest that you visit the lowest spots of your farm first.

 
Inspecting for damage:

• Foliage that has been damaged by frost will initially appear yellow and within a few days turn black usually towards the tips of the leaf first.
• If the growing point was not damaged, after 3 to 5 days of reasonably warm weather, new growth should appear from the whorl. If this occurs, then you can be assured that the growing point was not killed.
• Loss of leaf tissue at this early stage will have little if any effect on yield.
• Winter wheat at the tillering stage can withstand very low temperatures for a period of time (-11°C for less than 2 hours). Frost damaged winter wheat at this stage will have leaf chlorosis and necrotic leaf tips. However, the effect on yield will be slight.
• Frost damaged spring cereals will have wilted dark green and discolored leaves and will become necrotic at the leaf tips within 1 or 2 days after freezing. However, new leaf growth (normal green color) from the growing point should follow within 2 to 3 days. SL

Adapted from http://www.ag.ndsu.edu/smgrains/Frost2.htm and http://www.gov.mb.ca/agriculture/crops/cropproduction/faa23s00.html

Market News

Technical Analysis

Canola: November futures. The short and long term trend is up.
HRS Wheat: December futures. The short and the long term trend are down.
Corn: December futures. The short and long term trends are down.
Soybeans: November futures. The short term trend is down and long term trend is up.
Canadian Dollar: June futures. The short term trend is up and the long trend is down.
US Dollar Index: June futures. The short term trend is down and the long term trend is up.  
Crude Oil: June futures. Long term trend is up and the short term trend is down.